Hello,
First, congratulations on your weight loss! Losing 5% of your body weight can lead to significant improvements in health and quality of life. Second, are you sure that you need to lose 15 more pounds? Often people achieve the health goals they set, such as having more energy or working with my doctor to improve my cholesterol, but then seek to lose more weight because they have not reached their “goal weight”. Often this # is one that we randomly pick before we start a weight loss program. I recommend reviewing all of your initial goals and if you have achieved them, maybe you are at your goal weight. I also encourage a discussion with your physician to help determine a healthy goal weight for you. If your physician recommends losing more weight, ask him/her about adding in weight training to your exercise program. New research is showing weight management benefits from weight or strength training. You can also look at lifestyle activity. For example, yes I work out often, but can I get in more steps per day? How can I be more active at work or at home? Evaluating these others areas of physical activity might be helpful to you.
Here is a link to an article on weight loss plateau that might also be helpful: http://www.mayoclinic.org/healthy-lifestyle/weight-loss/in-depth/weight-loss-plateau/art-20044615